Lecture 1 Public health aspects of over and undernutrition_2023.pdf

Public Health Nutrition Nutritional status, diet-related illness, food security, over- and under- nutrition Dr Siobhan Hickling / School of Population and Global Health Learning Outcomes • Describe the key determinants and methods of assessing nutritional status • Describe the main health issues r...

Public Health Nutrition Nutritional status, diet-related illness, food security, over- and under- nutrition Dr Siobhan Hickling / School of Population and Global Health Learning Outcomes • Describe the key determinants and methods of assessing nutritional status • Describe the main health issues related to nutrition • Describe food security and the burden of over and under-nutrition • Describe some successful measures being undertaken to address over and under-nutrition Nutritional status • A dietary pattern is sufficient when it meets the needs of the individual and maintains the body composition and function of the otherwise healthy person. • This equilibrium can be disturbed by three processes: • • • decreased intake, increased requirements, altered nutrient utilisation. • Lack of nutrients results in metabolic changes • Over time disequilibrium results in anthropometric changes e.g. Iron status • Low intake • High requirements • Altered utilisation Nutritional status: State of health as it is influenced by the intake and utilization of nutrients 3 Assessing and monitoring nutritional status Assessment of nutritional status: Each of these involves collecting data in a variety of ways and interpreting each finding in relation to the others to create a total picture. Nutrition assessment part of total care - not always practical to assess each person in clinical setting • Medical history, physical exam body size/composition • Laboratory measurements for some aspects of nutritional status • Diet history/dietary assessment 4 Body size and body composition Tools: • Body mass index is used as a measure of overweight and obesity in populations • Waist circumference • Skinfold thickness • Bioelectrical impedance • DEXA (dual-energy X-ray absorptiometry) scans Each tools has advantages & disadvantages. BMI is most often used for population studies. 5 CLASSIFICATION OF OV E R W E I G H T & O B E S I T Y ...has been determined depending on optimal health for a given weight BMI BMI BMI BMI BMI 18.5 – 24.9 25 – 29.9 30 – 34.9 35 – 39.9 40 – ++ OVERWEIGHT OBESE above recommended weight for height excessive fat (adipose stores) SEVERE OBESE MORBIDLY OBESE Biomarkers of nutritional status • Rapid growth in research in biomarkers using metabolomics. • No biomarkers exist that can reliably and validly represent nutritional status • Key issues to address: • whether specific markers measure food intake or altered metabolism as a result of intake. • whether specific markers measure recent or habitual intake • repeated measures – repeatability of tests • Reducing cost • reference values for markers an estimation of quantitative measurements • Currently the limited biomarkers in use can: • Provide information on physiological effects of food consumption of certain nutrients only (iron status, nitrogen turnover) • Some could be used to validate dietary data collected • However much research continuing and is promising, nonetheless, 7 application of metabolomics will likely complement rather than replace traditional assessment of nutritional status Dietary Assessment • Involves taking a measure of what people eat during a given period of time. • Aim to capture ‘usual’ intake Which method do you think is best suited to assess intakes in large numbers of people ? • Traditional Methods: • 24 hour recall • Diet History • Diet record (3-7 days) • Food frequency questionnaire 8 24 hour recall Requires remembering everything eaten in past 24 hours Snapshot of foods eaten Advantages: ____________________________________ Disadvantages: __________________________________ 9 Diet History Usually conducted as an interview of usual dietary intake Many techniques exist, time reference period varies Advantages:_____________________________ Disadvantages:__________________________ 10 Diet record (1-7 days) Measure actual food intake based on prospective recording Can be weighed/unweighed Advantages: ____________________________________ Disadvantages: __________________________________ 11 Food frequency questionnaires 12 Food frequency questionnaires Serve Sizes Food frequency questionnaires Prompts participants with list of foods ‘usually’ eaten over reference period of time Often used in population surveys as relatively inexpensive Advantages:_____________________ 13 Disadvantages:____________________ Analysis of dietary data The Australian Food Composition Database • Dietary data is analysed using dietary analysis software • Assumptions often made based on food record • Software uses food composition database • Reference database that contains data on nutrient content of foods • Australian database • • ~1,500 foods & 250 nutrients per food Mostly analysed data, some imputed, from overseas or some calculated from recipes 14 The future of dietary assessment - newer and novel methods Web-based, CAT questionnaires Quick, easy, cheaper to administer Internal checks for missing, incomplete or implausible data, able to use photos serve sizes Immediate feedback to respondents Not accessible by all (ie computer literacy and access) Dietary recording apps Can record from list of food or enter own Can provide feedback on nutrient profile of food (pros and cons) TADA (Technology assisted dietary assessment) PDAs and mobile phones Preferred by many (esp children) to pen and paper Can record digital images – Analysis from image, reference image, standardization studies at present to validate image analysis for identification and quantification of food consumption 15 Skill and standard required for photos Optimisation of dietary assessment • Nutritional epidemiology relies on precise and accurate estimation of an individual’s usual food intake. • Although much research has been conducted in dietary assessment methodology there are still considerable limitations with conventional methods and new and novel methods. • Increased use of smart phones and the advent of machine learning may improve tools used to estimate food intake on both an individual and on a population level. 18 Dietary assessment = $$ Very few National Nutrition Surveys conducted in Australia PHAA propose moving to ongoing monitoring similar to NHANES model 19 Nutrition related illness Learning Outcome: • Describe the main health issues related to nutrition Key diet related health conditions in Australia Cancer Cardiovascular disease • Breast cancer, • Heart disease • Bowel cancer, • Stroke • Lung cancer, Prostate cancer, • High blood pressure • Head and neck cancers, Type II Diabetes Mellitus • Uterine cancer, Nutritional anaemia • Stomach cancers Gall bladder disease Overweight and Obesity Dental caries 21 Dietary variables as a risk factor for cancer The importance of food in the prevention of cancer has become increasingly recognised over the past three decades The cancer process • There are several hundred types of cancer, arising from different tissues • Cancer is characterised as a shared constellation of abnormal cell behaviours • Almost all solid tumours can be characterised by a relatively small number of phenotypic functional abnormalities, known as the hallmarks of cancer wcrf.org/cancer-process dietandcancerreport.org Diet, nutrition, physical activity and the cancer process wcrf.org/cancer-process dietandcancerreport.org Body fatness and the hallmarks of cancer Potential impact of diet, nutrition, physical activity and height in increasing susceptibility to cancer • Several exposures are linked to more than one type of cancer • Greater body fatness has systemic impact: - Hyperinsulinaemia - Increased oestradiol - Inflammation • These systemic factors affects a wide range of cellular and molecular processes that can subsequently promote cancer development and progression • This impacts the hallmarks of cancer via numerous mechanisms wcrf.org/cancer-process dietandcancerreport.org Findings: Summary of conclusions dietandcancerreport.org Recommendations – an overall package wcrf.org/cancer-prevention-recommendations dietandcancerreport.org Nutrition and cardiovascular disease There is a well-established link between dietary intake and chronic disease risk, particularly cardiovascular disease (CVD). Healthy dietary behaviours play an important role in the primary and secondary prevention of CVD. 28 The burden of CVD in Australia • • • • • • • CVD (heart, stroke, blood vessel disease) One of Australia’s largest health problems. Leading cause of death and disease burden Can be considered most costly disease – Health and economic burden of CVD exceeds that of any other disease and expected to increase >5% of hospitalisations as a principal diagnosis in Australia in 2018-19 25% of deaths in Australia in 2019 Deaths that are largely preventable Overall death rate fallen since 1960s and continues but appear to be slowing Patients with COVID-19 and pre-existing CVD are at increased risk of severe disease and death and COVID-19 itself can cause acute CVD injury. Australian Institute of Health and Welfare (AIHW) 2021, Heart, stroke and vascular disease, viewed 13 July 2022, https://www.aihw.gov.au/reports/heartstroke-vascular-diseases/hsvd-facts/contents/heart-stroke-and-vascular-disease-and-subtypes/total-heart-stroke-and-vascular-disease Most at risk… • Adults with type 2 diabetes: – 3-4 times more likely to develop CVD (~70% of those with type 2 diabetes have CVD) – ~ 75% of adults with diabetes die from CVD • Aboriginal and Torres Strait Islanders compared with other Australians are: – 2 times more likely to die from or be hospitalised for CVD – More likely to smoke, have ↑BP, be obese, suffer DM, drink alcohol at harmful levels, suffer ESRD • Australians in lowest SE-status group compared with highest are: – 43% higher rates of CVD – More likely to die from CVD – More likely to smoke daily, be obese and suffer DM • Australians in remote and very remotes areas compared with major cities are: – 30% more likely to die from or be hospitalised for CVD Major Risk Factors for CVD • Non-modifiable – – – – Increasing age Being male Ethnicity Family history • Behavioural risks – – – – Poor dietary quality Insufficient physical activity Smoking Alcohol consumption • Biomedical risks – – – – Overweight and obesity High blood cholesterol High blood lipids Impaired blood glucose regulation and DM Risk factor trends and disease trends • ~ 95% adults did not consume recommended amount of F & V • ~ 56% of Australians not getting enough exercise 2011-2012 ABS National Health and Nutrition Survey • Prevalence of obesity ↑ with now 67% adults overweight or obese • ↓ smoking rates by ~ 32% over past two decades with ~ 14% of Australians now daily smokers • 11% reported hypertension (↓ since the 1980s) • 23% had high blood pressure when measured • 6% high blood lipids • 5% diabetes (many more with impaired fasting glucose (pre-diabetes)) 2017-2018 ABS National Health Survey • 25% ↓ in the incidence of coronary events over the last decade. • ↓ in coronary heart disease deaths in hospital, suggesting better survival of those with the disease. • ↑ use of medications to ↓ blood pressure, ↓ blood cholesterol and antiplatelet drugs between 1997 and 2000 Current evidence for diet in prevention of CVD • • • • Healthy body weight ↓ saturated fat ↓ trans fat lowering blood cholesterol by diet • ↑ Omega 3 fats and fish • ↓ sodium ↑ potassium • Dietary fibre • Fruits and vegetables • Nuts and legumes • Dietary patterns : DASH Mediterranean Healthy/prudent Low GI/GL Portfolio, Weight loss, high protein Nordic *Nutrition Evidence Library, Technical Expert Collaborative on Study of Dietary Patterns †Collins C, Burrows T, Rollo M. Dietary Patterns and Cardiovascular Disease Outcomes: an Evidence Check rapid review brokered by the Sax Institute (www.saxinstitute.org.au) for the National Heart Foundation of Australia, 2017. Dietary patterns • Existing guidelines predominantly based on single nutrients • Research focus moving towards studying dietary patterns • A dietary pattern is the quantities, proportions, variety or combination of different foods, drinks and nutrients in the diet and the frequency with which they are habitually consumed* • A systematic review released in April 2017 reviewed dietary patterns and CVD outcomes† *Nutrition Evidence Library, Technical Expert Collaborative on Study of Dietary Patterns †Collins C, Burrows T, Rollo M. Dietary Patterns and Cardiovascular Disease Outcomes: an Evidence Check rapid review brokered by the Sax Institute (www.saxinstitute.org.au) for the National Heart Foundation of Australia, 2017. Dietary Patterns Key Features Mediterranean diet DASH diet High intake: fruit, vegetables, whole grains, beans/legumes, nuts/seeds, olive oil Moderate intake: Red wine, fish and dairy Low intake: Concentrated sugars and red meat Regular intake of fruits, vegetables, whole grains, legumes, nuts/seed, fish, poultry, reduced-fat dairy and foods rich in Potassium, Magnesium and Calcium Low intake: Saturated fat, total fat and foods high in sodium Healthy/ prudent Regular intake of fruits, vegetables, whole grains, fish, low-fat dairy, poultry, soy, diet olive oil Vegetarian diet High intake of Fruits, Vegetables, Grains/Legumes Little to no Meat consumption Nordic diet Regular intake of whole grains, fruits, vegetables, nuts, fish, rapeseed oil, reducedfat dairy Tibetan diet Regular intake of whole grains/cereals, meat, fruits, vegetables and beans Portfolio diet Largely Vegetarian diet with aim to lower plasma cholesterol. Low intake saturated fat High intake of fruits, vegetables, whole grains, nuts, plant sterols, fibre and soy protein Collins C, Burrows T, Rollo M. Dietary Patterns and Cardiovascular Disease Outcomes: an Evidence Check rapid review brokered by the Sax Institute (www.saxinstitute.org.au) for the National Heart Foundation of Australia, 2017. Majority of diets promoted consumption of: Fruits, Vegetables, Whole grains, Beans/legumes, Nuts/Seeds, Fish and Reduced-fat Dairy Primary prevention: The DASH diet appears to have the strongest evidence base for benefit in reducing CVD risk factors and CVD risk Secondary prevention: The Portfolio diet, followed by weight loss/calorie- restricted and DASH diet have the strongest evidence base for benefit Combined: The DASH diet had the most consistent evidence with improvements in blood pressure, blood lipids and body weight Food security, overnutrition and undernutrition Learning Outcome: • Describe food security and the burden of over and under-nutrition What is Food Security ? Food security: “when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy lifestyle.” • Food insecurity is linked to poverty • Food security is closely linked to economic and social health • Food security now and increasingly in the future will be strongly linked to climate change and population growth “ In the next 40 years, we need to produce as much food as the world has produced in the last 500 years. UN Food Systems Summit, September 2021 • Aims to foster healthier, more sustainable and equitable food systems 37 The State of Food Security and Nutrition, UN report 2019 • After decades of steady decline the trend in world hunger plateaued around 2015. 2018 > 820 million still hungry. Rising in: • • • almost all African sub-regions Latin America Western Asia • Estimated >2 billion do not have regular access to safe, nutritious and sufficient food. • 1/7 newborns suffered LBW • Overweight and obesity continue to rise in all regions • Conflict, climate variability and extremes are exacerbating the trends in poor food security. COVID19 also impact on food security • To safeguard food security important to have economic safeguards and social policies in place to counteract adverse economic cycles when they occur – this requires structural transformation to support lower SE regions Food Security Three key components of food security (World Health Organization, 2011) 1. Food access: the capacity to acquire and consume a nutritious diet, including: • • • • the ability to buy and transport food; home storage, preparation and cooking facilities; knowledge and skills to make appropriate choices; and time and mobility to shop for and prepare food. “ 2. Food availability: the supply of food within a community affecting food security of individuals, households or an entire population, specifically: • location of food outlets; • availability of food within stores; and • price, quality and variety of available food 3. Food use: the appropriate use of food based on knowledge of basic nutrition and care. 39 COVID-19 poses five major threats to global food security • Nations with poor health infrastructure and limited government capacity. • Nations with little to no safety net for citizens in the midst of a pandemic. • COVID-19 may prove especially deadly to those already suffering from extreme malnutrition and lack of access to food services. • Food shortages and food price spikes if swift action is not taken. • The global economy to slow or fall into a recession, exacerbating extreme poverty and hunger. 40 COVID-19 on Global Food Security • Impact and response varies by country and region • Global economic recession • Food system disruptions To traditional supply chains in LMIC (e.g. harvest, process, market, transport) Labour intensive activities in HIC (e.g. fruit picking, meat processing) Public and social nutrition programs disrupted or ceased Less access to health services (esp. vulnerable populations) • Must prepare food system for future 41 Causes of Food Insecurity - Poverty – ¼ of world’s population lives in poverty • National, household and individual levels of food insecurity • Poverty matches hunger worldwide • Causes and results in inadequate food production, distribution and storage “ -War, civil unrest, forced removal of people; refugees -Restrictions on trade, Economic policies, crops for cash -Lack of infrastructure; poor distribution of food -Disease epidemics e.g. HIV, Ebola (may affect agricultural workforce and transport of food into outbreak centres) -Cultural influences; e.g. gender bias in food access Both climate change and population growth will have a big impact on Food security directly and via causes identified above 42 Food as a weapon of war - Ukraine and Russia are major exporters of wheat (~25%), maize (~15%) and sunflower oil (~50% global trade) and around 12% global calories. Also major supplier of fertiliser for growing crops around the world. - Rapid spike in price and availability for these commodities. Prior to conflict cost and demand was high due to COVID-19 and weather events - A global food crisis is pending due to Russia’s invasion of Ukraine - The impact is felt most by the world’s poorest - Currently wheat in Ukraine still in storage (blocked ports for export) and next harvest due and will not be able to store. - Food insecurity and high cost of foods threatens political stability in all parts of the world. 43 Pending Future Predictable Causes of Food Insecurity - Population growth Between 1950 and 2010, the world’s population increased from 2.5 to 6.9 billion and by 2050 is expected to be 9.3 billion. To support this increasing population, food production will need to double by 2050. “ With more people living in cities, it is likely that food supply and demand will be affected. Globally, urban dwellers generally eat more - Climate change meat and dairy foods and less fibre-rich grain foods, whereas rural dwellers eat more cereals, tubers and roots. Globally many climate change factors affecting food production In Western Australia over the past 3 decades salinity of soils has increased  decreased land available for agriculture Rainfall has decreased which has affected crop yields 44 The two faces of food insecurity Malnutrition: A state of physical impairment where the individual can no longer maintain natural bodily capacities such as growth, pregnancy, lactation, learning abilities, physical work, as well as resisting and recovering from disease. The term includes micronutrient deficiencies, stunting, wasting, underweight, as well as overweight and obesity. Under-nutrition Food Insecurity Over-Nutrition 45 Under-nutrition Hunger and under-nutrition are devastating problems • Two billion people world suffer from various forms of malnutrition. • Malnutrition - underlying cause of death of 2.6 million children/year - a third of child deaths globally. • 1 in 4 of the world’s children are stunted; in developing countries this is as high as one in three; this results in failure to develop fully. • Undernutrition accounts for 11 per cent of the global burden of disease and is considered the number one risk to health worldwide • Adults who were malnourished as children earn at least 20% less on average than those who weren’t. Under-nutrition caused by - Inadequate energy/nutrient intake - Disease 46 The inter-generational cycle of under-nutrition Inadequate food and health care PREGNANT WOMEN Low weight gain Increased maternal mortality INFANTS Low birth weight, High mortality Impaired mental development Increased risk of chronic disease ADOLESCENTS Stunted growth Decreased physical capacity ADULTS Malnourished Poor productivity in the workforce Inadequate food and health care Inadequate food and health care Frequent Infections CHILDREN Stunted Growth Reduced mental capacity Impaired Immunity Frequent Infections The cycle of infection and under-nutrition Weight Loss Growth faltering Lowered Immunity and Resistance Lowered Defence Barriers Inadequate Dietary Intake Disease Incidence, Severity, Duration Appetite Loss Nutrient Loss Malabsorption Altered Metabolism Overnutrition and undernutrition Learning Outcome: • Describe some successful measures being undertaken to address over and under-nutrition Solutions to Food Insecurity and undernutrition Short term solutions • 50 Emergency relief for famine • Food supplementation • Food fortification Long term solutions • Education • Limit wastage • Improve trade policies • Sustainable agriculture; • Development and sharing new technologies • Alleviate poverty, inequality, climate change … (UNDP Sustainable Development Goals) • EAT Lancet Great Food Transformation Food Production is a threat to climate stability “Global food production threatens climate stability and ecosystem resilience. It constitutes the single largest driver of environmental degradation and transgression of planetary boundaries. Taken together the outcome is dire. A radical transformation of the global food system is urgently needed. Without action, the world risks failing to meet the UN Sustainable Development Goals and the Paris Agreement..” Professor Johan Rockström Co-chair The EAT Lancet Commission of Food, Planet, Health 2019 51 Healthy Diets from Sustainable Food Systems “Transformation to healthy diets by 2050 will require substantial dietary shifts. Global consumption of fruits, vegetables, nuts and legumes will have to double, and consumption of foods such as red meat and sugar will have to be reduced by more than 50%. A diet rich in plant-based foods and with fewer animal source foods confers both improved health and environmental benefits.” Professor Walter Willet Co-chair The EAT Lancet Commission of Food, Planet, Health 2019 52 Double pyramid Environmental impact of food choices Five Strategies for a Great Food Transformation Strategy 1: Seek international and national commitment to shift toward healthy diets Strategy 2: Reorient agricultural priorities from producing high quantities of food to producing healthy food. Strategy 3: Sustainably intensify food production to increase high-quality output Strategy 4: Strong and coordinated governance of land and oceans Strategy 5: At least halve food losses and waste, in line with UN Sustainable Development Goals Over-nutrition The other face of malnutrition Over nutrition is a growing problem in developing countries - why ? 1. Improved economic conditions 2. Increased access to food 3. Change in diet and lifestyle patterns to more like developed countries Nutrition Transition 55 Traditional, Rural Diets Low-fat Low-sugar High-fibre Monotonous, little variety Mainly CHO Inadequate in energy and/or nutrients Disease & Lack of Medical Care Undernutrition Increased risk of infection NUTRITION TRANSITION Adequate and prudent Affluent modern, Western Diets High-fat High-sugar Low-fibre Diverse, varied High in animal protein Nutritionally adequate but imprudent Inactivity Smoking Alcohol Stress Optimal Nutritional Status Lower risk of chronic and infectious disease Obesity Coronary Heart Disease Diabetes Hypertension Stroke Overnutrition and Chronic Disease Over-nutrition is strongly associated with chronic disease - essentially through excess energy intake and insufficient micronutrient intake = energy-densenutrient-poor diets • Weight gain, obesity – global obesity epidemic: 2/3 adults and 1/4children in Australia are overweight or obese; • Type 2 Diabetes Mellitus (T2D) – foods with high glycemic index (causing a rapid rise in blood glucose after eating); prediabetes and T2D are increasingly seen in obese children; low fibre intakes mean we do not feel as satiated after eating; fibre helps regulate glucose metabolism; • Cardiovascular disease (excess energy, fat, saturated fat, low antioxidant and fibre intakes) – polyphenols in fruits and vegetables hold therapeutic promise due to their vasodilatory effects • Cancer – low fibre, excess alcohol, red meat and overweight/obesity are risk factors for some cancers, including bowel and breast cancer 57 AUSTRALIAN HEALTH SURVEY 2011-12 OVERWEIGHT ADULTS 63.4% 1.50% •Men 35% OVERWEIGHT 25% 26% Sub-groups at increased risk 35.20% NORMAL (up from 61.2% in 2007-08 and 56.3% in 1995) 21% UNDERWEIGHT •Rural and remote locations 28.30% OBESE •Low SES women If current trends continue, in 2025 •Indigenous Australians 83% 75% 83% of men & 75% of women Will be overweight or obese MEN 1995 2007-8 2011-12 Children 5-17years WOMEN Rates of Obesity and Overweight Persons by Country 2010 Percentage of Adult population 80 OVERWEIGHT 60 40 20 OBESITY 0 0 5 10 15 20 25 30 35 40 Summary of the strengths of evidence on factors that might promote or protect against weight gain and obesity in adults. EVIDENCE DECREASES RISK INCREASES RISK Regular physical activity High dietary fiber intake High intake of energy- dense foods* Sedentary lifestyles Physical inactivity Quitting smoking Home and school environments Heavy marketing of energy dense foods and fast foods outlets Adverse social and economic conditions Sugar-sweetened soft drinks and juices Possible Low glycaemic index foods Breastfeeding Large portion sizes High proportion of food prepared outside of homes Fad dieting Limited Increased eating frequency Alcohol Convincing Probable Source: A literature review of the evidence for interventions to address overweight and obesity in Adult and older Australians. The Australian Government Department of Health and Ageing, October 2005. Low-fat ad libitum eating plans are most effective for 01 long-term weight loss (fad diets/crash diets do NOT DIET MAIN STRATEGIES TO CONTROL OBESITY Difficult to lose weight with increased PA alone, however, is key factor of behavioural modification (for long-term weight loss) AT THE INDIVIDUAL LEVEL result in long-term weight loss) 02 EXERCISE Appetite suppressants and lipase inhibitors - short-term use only, unfavourable side effects Herbal remedies – not effective for weight loss 04 Green tea extract – some suggested benefit of a very small increase in MAIN STRATEGIES metabolism - long term weight loss unknown, clinical significance unknown TO CONTROL SURGERY OBESITY 03 MEDICATIONS AT THE INDIVIDUAL LEVEL A medical approach to a lifestyle disease - most effective for severely obese patients (BMI>40) , cost effective for the severely obese Weight loss observed and other risk factors improved and maintained for 1-2 years, some regain. calorie intake drastically reduced, often diet quality remains poor – albeit with smaller portions HOW EFFECTIVE ARE THESE STRATEGIES SUMMARY OF WEIGHT MANAGEMENT INTERVENTIONS Lifestyle change Combined lifestyle change and pharmacotherapy Bariatric surgery with maintained lifestyle change INTERVENTION LEAST EFFECTIVE (>10% weight loss in few studies; weight loss not likely to be maintained in most participants) Dietary change—3–5 kg at 12 months; 0 kg at 5 years Dietary change and exercise—5– 10 kg at 12 months; 0–3 kg at 5 years Exercise—0 kg at 12 months; 0– 5 kg at 5 years Lifestyle change and psychological intervention—3– 4 kg at 5 years MODERATELY EFFECTIVE (>10% weight loss across some but not all studies; weight loss maintained >5 years in some but not all participants) Medication (e.g. orlistat) and dietary change—6– 10 kg at 12 months; 2– 3 kg at 5 years MOST EFFECTIVE (consistently >10% weight loss across studies; weight loss likely to be maintained >5 years) • Laparoscopic adjustable gastric banding—20% at 12 months; 12% at 10 years • Vertical banded gastroplasty— 20% at 12 months; 15% at 10 years • Roux-en-Y gastric bypass—33% at 12 months; 30% at 10 years Source: National Health and Medical Research Council (2013) Clinical practice guidelines for the management of overweight and obesity in adults, adolescents and children in Australia. HOW EFFECTIVE ARE THESE STRATEGIES Severe obesity difficult to treat Frequently ineffective in helping severely obese lose enough weight to improve QOL and health Lifestyle interventions and pharmacotherapy are only modestly effective in promoting weight loss and improving comorbidities However, longterm effectiveness and safety represent a critically important gap in the research Bariatric surgery increased in prominence as most effective treatment for severe obesity WHAT DO WE NEED TO DO? The causes of obesity are complex and multifaceted pointing to a range of different solutions. At the heart of the issue is the energy balance equation. The physiology of the human energy balance equation is not well adapted to the changing world and has not kept pace with human evolution and development over the past 50 years TARGETING OBESITY VIA PUBLIC POLICY Prevention and Management of Overweight and Obesity in Australia Policy PHAA’s Food and Nutrition Special Interest Group. Date policy adopted: September 2019 PHAA will 1 Advocate that federal, state and territory governments: a. Establish overweight and obesity as a national priority; b. Lead an effective approach to tackling this issue; c. Allocate funding to support development, implementation, evaluation and research around a national healthy weight plan; 2 Monitor progress on the implementation of these recommendations and report back to members; 3 4 5 Partner with other organisations to jointly influence action for population prevention of overweight and obesity; Contribute to policy and advisory forums about the promotion of healthy weigh for children, young people and adults; Inform and mobilise its members in support of this policy. What else? SUGAR TAX? FAT TAX? BARIATRIC SURGERY EN MASSE? TOWN PLANNING 01. Failure to act early already having significant and undesirable consequences 02. Policy discussions vibrant but not yet matched by positive change by society, governments and economy 03. Environmental determinants remain misunderstood, under-researched and policy drifts towards individual responsibility 04. 05. A danger that the time to act has passed and unable to reverse population-wide obesity Being normalised even as trend accelerates and grows KEY POINTS 01. There are significant gaps the evidence base for effective intervention for overweight and obesity prevention 02. There are few interventions that successfully reduce the prevalence of overweight and obesity and none on a population scale, but some examples are showing promise 03. Action needed now when evidence is imperfect and incomplete 04. No ‘magic bullet’ that is either cost-effective or sustainable WE NEED 01. A system-wide approach, redefining the nation's health as a societal and economic issue 02. Higher priority for the prevention of health problems, with clearer leadership, accountability, strategy and management structures 03. Engagement of stakeholders within and outside Government 04. Long-term, sustained interventions 05. Ongoing evaluation and a focus on continuous improvement 06. Otherwise...